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The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Number of shares authorized for issuance under share-based payment arrangement.

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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Note 8 - Stock-based Compensation (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2019
Share-based Payment Arrangement, Expense, Tax Benefit
Deferred Compensation Plan for Directors [Member]
Deferred Compensation Arrangement with Individual, Compensation Expense				$ 0	$ 0
A 2014 Long-term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)	5,600,676			5,600,676
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)	2,359,333			2,359,333
Share-based Payment Arrangement, Expense, Tax Benefit	$ 0		$ 0
A 2014 Long-term Incentive Plan [Member] \| Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)				10 years
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	0			$ 0
A 2014 Long-term Incentive Plan [Member] \| Share-based Payment Arrangement, Option [Member] \| Share-based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage				50.00%
A 2014 Long-term Incentive Plan [Member] \| Share-based Payment Arrangement, Option [Member] \| Share-based Payment Arrangement, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage				25.00%
A 2014 Long-term Incentive Plan [Member] \| Share-based Payment Arrangement, Option [Member] \| Share-based Payment Arrangement, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage				25.00%
A 2014 Long-term Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement By Share-based Payment Award, Performance Threshold, Operating Income				$ 1,000
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 151			$ 151
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)				1 year 80 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value				$ 190
A 2014 Long-term Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)				2 years
A 2014 Long-term Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)				4 years
A 2014 Long-term Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Share-based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage				0.33%
A 2014 Long-term Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Share-based Payment Arrangement, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage				0.33%
A 2014 Long-term Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Share-based Payment Arrangement, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage				0.33%